Smoke simulation values are Resetting automatically
This is because you are turning the domain  into an emitter and then back into a domain.

Each smoke type (domain, flow, collision) plays a different role in the simulation with different settings. By clicking that button, you are changing the active object to a different type.

Generally you'll want to select one of the smoke types for each object and leave them at that. Domain options should be set on the domain object and flow settings set on the flow object(s).

For example, here's a quick setup:



Note that to access the different settings for the domain and flow objects I select the object in question.